MVC Unit Testing Asserts with Rhino Mocks

When I first started learning to use mocking frameworks I was lucky enough to start on Moq which was nice and simple. Whenever I needed to know something there was one single google code page which told everything. Nice! Rhino Mock by example I find hard work, so I put this cheat sheet together to help get up and running quickly.

Rhino Mock Asserts

	public void RhinoMockExampleAsserts()
	{
	// Example assert _principal.IsInRole(..) wasn't called
	_principal.AssertWasNotCalled(x => x.IsInRole(Arg<string>.Is.Anything))
	// Assert API call was made
	_apiClient.AssertWasCalled(x => x.GetCustomerStatement(Arg<int>.Is.Anything));
	// Assert API call was made with a specific ID
	_apiClient.AssertWasCalled(x => x.GetCustomerStatement(Arg<int>.Is.Equal(200));
	// Was called 3 times
	_principal.AssertWasCalled(x => x.IsInRole(Arg<string>.Is.Anything), x => x.Repeat.Times(3));
	// Was called once
	_principal.AssertWasCalled(x => x.IsInRole(Arg<string>.Is.Equal(usersGroup)), x => x.Repeat.Once());
	// Accessing parameters from a called method using Rhino Mock
	// _sessionTokenWriter.WriteSessionTokenToCookie(ClaimsPrincipal cp)
	var mockArgs = _mockSessionTokenWriter
	.GetArgumentsForCallsMadeOn(
	x => x.WriteSessionTokenToCookie(Arg<ClaimsPrincipal>.Is.Anything),
	x => x.IgnoreArguments()); // setupConstraints(?) is of type Action<IMethodOptions<object>>
	// mockArgs is IList<object[]> a list of arrays.
	// Where mock[i][n] where i is number of calls? And n is the nth parameter in that call?
	var claims = (mockArgs[0][0] as ClaimsPrincipal).Claims;
	}

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MVC Asserts

	public void ExampleMvcAsserts()
	{
	// Setup an error in the model so that ModelState.IsValid returns false.
	// Used to check that the ModelState.IsValid check is in place.
	controller.ViewData.ModelState.AddModelError("Surname", "The Surname field is required.");
	// Call the controller method. This usually returns an ActionResult, which may need to be cast.
	var result = _userController.Create(user).Result;
	// Assert that the redirect result is of a particular type
	Assert.That(result, Is.TypeOf<RedirectToRouteResult>());
	// Assert that the controller redirects to the correct view
	Assert.AreEqual("Index", ((RedirectToRouteResult)result).RouteValues["action"]);
	// Check manaully added model state errors
	Assert.IsTrue(controller.ModelState.Keys.Contains("Email"));
	Assert.AreEqual("The Email address is already in use.", controller.ModelState["Email"].Errors[0].ErrorMessage);
	// Check the model class is returned correctly in the view.
	var userModel = viewResult.Model as User;
	Assert.AreEqual(userModel.Forename, "John");
	}

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Aysnc Considerations

	public void AsyncExamples()
	{
	// Async controller actions have to be called asyn:
	await controller.Create(model);
	// Async methods return a task, so use Task.FromResult:
	_apiClient.Stub(x => x.GetCustomersAsync(Arg<long>.Is.Anything))
	.Return(Task.FromResult(new List<Customer>()));
	// If the method returns just Task and not Task<T> use true/null/1:
	_file.Stub(x => x.SavePostedFile(Arg<HttpPostedFileBase>.Is.Anything))
	.Return(Task.FromResult(true));
	}

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